Department of Agriculture and Immi- 
gration of Virginia 

GEO. W. KOINER, Commissioner 

In co-operation with the Forest Service United ^States 
Department of Agricnlture 

Henrv S. Gra\p:s, Forester 



SHORTLEAF PINE IN VIRGINIA 

The Increase in its Yield by Thinning 



By W. W. ASHE 

Forest Examiner, Forest Service 



RICHMOND: 

IJAVIS UOXroM, .SUPERINTENDENT FTPLK; PKINTING 
]5)13 




PLATE 1. 
(."rowded small pole stand of shortleaf pine about 30 years old in need of 
thinning. The trees are slender and clean stemmed, but irregular in size A large 
number of the smaller trees should be removed. 



Department of Agriculture and Immi- 
gration of Virginia 

GEO. W. KOINER, Commissioner 

In co-operation with the Forest Service United States 
Department of Agriculture 

Henry S. Graves, Forester 



SHORTLEAF PINE IN VIRGINIA 

The Increase in its Yield by Thinning 



By W. W. ASHE 
Forest Examiner, Forest Service 



RICHMOND: 

DAVIS BOTTOM, SUPERINTENDENT PUBLIC PRINTING 

1913 



'•p fc 



\1 



SEP 15 19'.9 



CONTKNXS 



Purposes and results 5- 

Distribution and importance <6 

Names and distinguishing claaraoteristics 7 

Uses of wood ^ 

Condition and composition of old-field stands 9s. 

Permanency of old-field pine stands 10 

Management lii. 

Fully stocked and crowded stands .- 13. 

Understocked stands 14 

Thinnings 15. 

Classes of trees 15. 

Dominant trees 15 

Intermediate trees 15 

Suppressed trees 16 

How heavily to thin ItJ 

What to remove in thinning 1'^ 

Acceleration in growth from thinning 17 

Method of thinning m 

Sapling stands (younger than 20 years; 18 

Small pole stands (from 20 to 30 years old ) 18 

Large pole stands (from 30 to 40 years old ) 19- 

Mature stands (from 40 to 50 years old) 19 

Typical stands 20 

Production of cordwood from thinned and unthinned stands 23 

Maximum yield of cordwood 24 

Cost of growing cordwood 2& 

Production of saw timber 26 

Influence of density of stand upon yield of saw timber at 

different ages 2'' 

Age of cutting for maximum yield . 2« 

Cost of growing saw timber 2^ 

Value af trees and stands 32 

Waste in cutting small trees 35 

Lumbering and restocking 35 

Isolated seed trees 3b" 

Cutting in strips 37 

Cutting unthinned stands 37 

Planting waste land 38 

Returns from plantations 39 

The protection of stands 41 

Fires 41 

Insects 43 

Fungus diseases 44 



It^UUSTRATPIONS 



Plate I. — ^Crowded small pole stands of shortleaf pine about 30 
years old in need of thinning. The trees are slender and clean 
stemmed, but irregular in size. A large number of the smaller 
trees should be removed Frontispiece. 

Plate II. — A dense sapling stand of shortleaf pine 15 to 18 years 
old, but too small to be profitably thinned. While the clean 
condition of the floor is good, fire could do great damage to 
such a stand 

Plate III. — Understocked large pole stand of shortleaf pine 30 
years old. The trees are short-bodied and knotty and will yield 
only low grade lumber. The best that can be done with such 
a stand is to cut it, leaving the most slender, clean-bodied 
trees for seed-trees 

Plate IV. — Crowded, large pole stand of shortleaf pine 40 years 
old, badly in need of thinning by removing the smaller pines 
and many of the hardwoods. Condition of larger trees, with 
long, smooth bodies, excellent 

Plate V. — 'Mature stand of shortleaf pine. Trees nearly uniform in 
size and ready to be cut for lumber. Groups of slender, wind- 
firm trees can be left- for seed trees, 

Plat" VI. — Figure 1. — A typical case of sustained rapid diameter 
growth, resulting from repeated thinnings, in a tree of short- 
leaf pine which was overcrowded for many years. Wood of 
.'such a tree is free from large knots, and its stum page is 
worth $8 a 1,000 board feet under a cost of operating of $12 

li'igure 2. — Stem of a small sprout sapling of shortleaf pine, 
crooked and scarred at the neck as a result of the original 
seedling having been killed to the ground by fire. Stump and 
root rots gain entrance through such scars. 



Shortleaf Pine in Virginia 



The study upon which this report is based was undertaken by 
the Forest Service in co-operation with the State of Virginia, the 
worlc being done under the direction of tlie officer in charge 
of State Co-operation in the Forest Service. By ithe terms of the 
co-operative agreement, the State is authorized to publish the find- 
ings of the investigation. 

PURPOSES AND RESULTS. 

At the request of Hon. C. A. Swanson, Governor of Virginia, 
the Forest Service, United States Department of Agriculture, in 
the autumn of 1909, made an examination of the second-growth 
shortleaf pine in old fields in the middle portion of Virginia. 
The cost of this work was borne jointly by the State of Virgiiiia 
and the Forest Service. 

The examination includevl.a detailed investigation of stands of 
pine in old fields in Mecklenburg, Lunenburg, Brunswick, and 
Hanover counties, which was supplemented by a general examina- 
tion of the stands in other counties in the middle part of the State. 
Its scope was: 

(1) To ascertain the condition of the old-field stands and the 
value of their timber for lumber uses; 

(2) To determine the eli'ect of lumbering on the future yields 
of the stands and to ascertain whether conservative methods of 
cutting could be employed profitably; 

(3) To determine the yield of stands of different ages; 

(4) To recommend methods of thinning and cutting to ac- 
celerate growth; 

(5) To devise methods of protection for young growth. 

The conclusions reached as a result of the investigation can be 
summarized as follows: 

Shortleaf i)ine is the most important tree in twenty south- 
central counties, but the yield from the pine lands is low because 
there is neither protection nor a definite system of cutting. The 
yield can be greatly increased and the quality of timber improved 
by a regular system of management. 

(1) Better protection against fires and insects is required in 
most stands. Young stands, especially while in process of stocking, 



C SHORTLEAF TINE TX A IKCIX lA 

Slitter most from fires. Older stands are most endangered by in- 
sects. Protection against fire may be secured by means of fire 
lanes, posted warnings, restriction of nigtit hunting, and patrol 
during dry seasons Avhen neighboring lands are afire. The danger 
of loss from insects may be reduced by making frequent thinnings 
and by removing or by cutting infested trees. 

(2) The average stand of pine is far too thinly stocked. This 
is due to insufficient natural seeding and to the thinning of young 
stands by fire and of older stands by insects. The yield of such 
thinly-stocked stands is considerably less, and the grade and vahie 
of the timber is lower, than from thickly stocked stands. 

(3) Crowded areas occur in nearly all stands, and some stands 
are crowded throughout. Such crowded plots can be greatly im- 
proved by thinnings. The ett'ect of thinnings is to accelerate 
growth, hasten maturity, and produce a superior quality of timber. 
The beneficial results of thinnings decrease with the age of the 
stand, but stands as old as forty-hve years respond to them well. 

(4) Where naturaf seeding has not formed dense stands with- 
in ten years, the stocking can be completed by the planting of 
seed; and, where natural seeding does not take place, whole areas 
may be seeded. Stands restocked in these ways can be expected to 
yield fully as Avell as the best natural stands and to return a fair 
rate of interest on their cost. 

If management is applied, that is, if young stands are pro- 
tected, full stocking secured, and the stands subsequently thinned, 
the yield of saw timber fi^om a 40-year-old stand can be more than 
doubled and its value greatly increased. Shortleaf pine is already 
one of the chief sources of building material on the farms. Pair- 
thermore, the farms have more timber than is required for then- 
own support, so that as the general demand for coarse lumber in- 
creases and its price rises, shortleaf pine in farm woodlots can be 
made an important source of commercial timber and a means of 
permanent income. 

DISTRIBUTION AND IMPORTANCE 

Second-growth or old-field shortleaf pine is the most important 
tree of middle Virginia and the Piedmont, south of the Rappa- 
hannock, in which region it probably occupies more than one-half 
of the total forest area and more than three-fourths of the farm 
forest area. It forms the dominant growth on more than 3,000,000 
acres, on which it occurs either in, pure stands or, more commonly, 



SlIORTLEAF PINK IX VIKCIXIA 7 

with u slight mixture of other pines and of seedling and sprout 
hardwoods. It meets with least competition and forms the i)urest 
second-growth stands in the tier of southern counties west of Lun- 
enburg county. It is not common iu)rth of the Eappahannock 
river, and is infrequent on the Blue Eidge mountains and in the 
Great Valley, while in I'idewater Virginia it grows only on the 
best drained clay soils, and in these sections, on account of the com- 
petition of other species, its second grow^th seldom occurs in pure 
stands. 

Xames and DlSTlNGUISniXG ClIARACl'ERISTICS 

Shortleaf pine is also and more generally known as rosemary 
pine, spruce pine, and yellow pine. The original growth is fre- 
(juently distinguished from the second growth in old fields under 
the names of forest or woods pine. 

I'his tree is not to l)e confused with scrul) or jack pine, 
which is also called spruce pine. Scrub pine is a smallei- and in- 
ferior tree with a limby stem and smooth, scaly bark. It is largely 
replacing shortleaf pine in old fields in the northern portion of the 
State and in the upper edge of the Piedmont in and near the 
mountains, and is occasionally found mixed witli shortleaf pine 
•southeastward as far as Brunswick county. Xor is it to l)e con- 
fused with loltlolly pine, which is kncnvn in extreme southern \'ir- 
ginia as shortleaf pine and. where it occurs near the cuast. as long- 
leaf, swamp, foxtail, or slash pine. Lol)lolly i)ine is the common 
pine on sandy soils in Tidewater Virginui. but it extends westward 
in association with shortleaf pine to T)runswick. Chesterfield and 
Louisa counties. The northern i)itch. bull, or black pine of the 
mountains, which is yet another tree, seldom forms second growth 
in old fields. 

The cone and leaf differences of these trees will be a further 
lielp in sei)arating them: 

Shortleaf pine has cones (burrs) seldom more than 1 l-'2 inches 
long, and slender, straight neeflles. two or three together, twice as 
long as the cones. 

Scrub pine has cones of about the same length as tho^e of 
shortleaf pine (1 1-2 inches) but they are relatively broader. The 
needles are stout and twisted, with never more than two together, 
and are about the same length as tlie cones. Freciuently the cones 
of sci'ub pine and shortleaf pine remain on the ti-ees for nuuiy years 
after opening. 



8 SHORTLEAF PIXE IN VIRGINIA 

Loblolly pine has large cones, from 3 to 4 inches long. Its 
needles are borne in threes and are about twice as long as the cones. 
The cones of this species usually fall during the second summer, 
but sometimes they persist for several years. 

Uses of Wood 

The timber of second-growth shortleaf pine is largely sap- 
wood. The formation of heart wood does not begin until the trees 
are about twenty-five years old. For many years thereafter the 
heartwood is limited to a small core, and more than two-thirds of 
the volume of trees fifty years old is still sapwood. The most im- 
portant uses for the wood of the shortleaf pine are for building 
lumber, fuel, slack cooperage, box lumber, headings, and crates. 
The wood contains too much resin to be a desirable material for 
paper pulp stock without special treatment, although it is used to 
some extent for this purpose. On account of its softness it is not 
suited for railroad ties if the traffic is hea\'y\ and, when used for 
this purpose should be made more durable by preservative treat- 
ment. 

'J'he large proportion of sapwood in the second-growth tiin- 
ber renders it undesirable for shingles, for which the durable lieart- 
wood of the old growth was extensively employed ; and imfits it for 
other uses requiring exposure to the weather, unless it is thoroughly 
IdJn-dried and painted. Logs more than fourteen inches in dia- 
meter from trees with clear boles yield lumber suitable for ceiling 
styles and panels of doors, sashes, window frames, interior wood- 
work, and also for flooring if rift sawed. Timber suitable for such 
uses must come not only from comparatively large trees, but from 
trees which early cleaned their stems and formed wood in the lower 
two-thirds of the trunk free of Imots. That part of the tree which 
can be converted into lumber of this kind should command, on the 
basis of $25 for the finished lumber, a stumpage price of not less 
than $10 a thousand board feet. 

Unless the pri<'e of cordwood. stumpage is proportionately 
much higher than that of saw timber stumpage, the greatest profit 
from a crowded stand will be secured by reserving the larger trees 
for saw timber, and in the meantime thinning or culling the small- 
CvSt trees for cordwood, stave stock, box boards, bolts, and similar 
purposes, for which small material is suited. If only selected trees 
are retained for saw timber they should be allowed to attain a large 
size in order to produce timber of high quality. 




PLATB II. 
A dense sapling stand of shortleaf pine 15 to 18 years old, but too small to be 
profltably thinned. While the clean condition of the floor Is good, fire could do 
great damage in such a stand. 



SIIORTLEAT PINE IN VIROINIA V 

CONDITION AND COMPOSITION OF OLD-FIEi^D 
STANDS 

As early as 1735 it had become a fixed part of the farming 
system of middle Virginia to clear new ground each year and to 
abandon to tallow a parcel of the oldest and most worn farming 
land. The land tiius turned out was rapidly colonized with pines 
through seed blown by the wind from old trees nearby. When 
these pines had become large enough and the humus had been re- 
stored to the soil through them, the land was usually cleared again. 
Such a system of rotation of timber and cultivated crops was pos- 
sible only in a region where land was abundant and cheap. It was 
due in part to the lack of local markets, which made it necessary to 
export a large portion of the crops and therefore to produce them 
as cheaply as possible, regardless of the eli'ect upon the soil; and 
in part to the fact that these soils were not natural grazing lands, 
and the depleted humus could be renewed naturally and cheaply 
by the replacement of the native pines. Some of the existing 
groves of old-held pine thus originated before the Revolutionary 
W^ar. Most of them, however, are younger, having originated dur- 
ing and just after the Civil War or in the subsequent periods of 
agricultural depression about 1880 and 189-2. These stands are 
consequently of all ages; from the youngest, just in process of 
stocking land which has been turned out during the past decade, 
to those more than 100 years old. Stands between tifteen and 
forty-five years old are, however, the most numerous. 

Such old-field stands were thus established naturally, and no 
efforts were made by the owners to increase their density Avhen 
they wei-e too open or to i)rotc('t them, while young, from fire. 
They have seldom been thinned judicionsly for improvement. As 
a result, they vary widely in density. Small tracts are usually 
well-stocked, since, if seed-bearing trees were nearby while stocking 
was taking place, seeds were in a few years scattered uniformly 
over the entire tract and such small tracts were often protected 
from fire by fences, or by adjacent cultivated fields. The trees in 
such well-stocked stands are slender and clean-bodied, with small 
crowns. The average tract, however, is poorly stocked. The trees 
are isolated, individually, or in irregular groups, and conseciuently 
short-bodied, knotty, and coarse-grained. This open condition of 
many of the stands is due to the fact that seed trees were too 
few or too distant while the stocking Avas in progress, or to the 
fact that the fields became grassv and the seedlings Avere killed by 



10 SHOKTLEAF PINE IN VIRGINIA 

fires that burned the grass. Scattered advance growth frequently 
has borne seed and so stocked the gaps. Such stands are irregular 
in age and size. 

Many of the older stands have been irregularly and often heav- 
ily cut for poles, cordwood, and even sav^logs. Most stands of sap- 
ling or larger size are too open for the best growth of the trees 
and for the highest financial returns. 

The proportion of shortleaf pine in the old-field stands varies. 
-North of the Eappahannock river the proportion of scrub pine 
mixed with the shortleaf increases, until in Fairfax county and the 
lower end of Prince William county it largely replaces shortleaf 
pine. It is also largely mixed with shortleaf pine in stands near 
the mountains. In the shortleaf pine stands in the eastern ends of 
Hanover, Chesterfield and Brunswick counties, there is a large 
proportion of loblolly pine, which entirely supplants the shortleaf 
farther eastward. South and southwest of Hanover county the 
only pine in the field stands is the shoi-tleaf, but species other than 
pine form part of the mixture in a varying proporticm, though 
they seldom make up more than ten per cent, in stands younger 
than thirty-five years old. In young stands these associated species 
vary Avith the kinds of seed-trees nearby. On lower slopes they 
are usually maple, poplar, sweet gmn. and the oaks; on hilltops 
they are red cedar, oaks, hickory, black gum. persiniinon. cherry, 
thorn, sassafras, and dogwood. 

Permanency of Old-Field Pine Stands 

As the field pine stands become older. es]:)ecially after they 
have passed the thirty-fifth year, their crown cover tends to thin, 
and this favors the growth of the oaks and hickories, which come 
in from seed dropped by squirrels, crows', jays. etc.. and are better 
able to grow beneath the cover than are young pines. Even after 
the pine in the stand begins to seed the proportion of these broad- 
leaf species continues to increase, since the young pines can come 
in only when an extensive opening is made by the death of a large 
\Vu\e. There is thus a tendency toAvard a gi-adnal re-establishment 
of the oi'iginal forest type Avhich prevailed l>efore the land Avas 
cleared, namely, a mixture of oak. hickory, black gum. and pine, 
with pine forming a small proportion on the best soil and a large 
proportion— frequently more than half the number of trees — on 
the poor, dry or sandy soils. The pure pine stands are. therefore, a 
temporary type. Avhich in time Avill be re])laced by the permanent 
mixed-growth type. 



SHORTLEAF PINE IX VIRCIXIA 11 

It is not Jin invariable rule that "•hardwoods follow pine" after 
nittmg or that "pine follows hardwoods'" after cutting or clearing. 
But pure pine usualty forms the second growth if there is no shade 
or cover, as in old fields or on hardAvood land which has been cut 
clear in late summer or early antumn. when the sprouting power of 
the hardwoods is low. If seed-bearing trees are near, such open 
land, whether in field or forest, is captured in a few years by 
pine, by means of its abundant, light seeds which are widely scat- 
tered by the wind. The heavy seeds of oak, hickory and black 
gum. which are Carried iai'gely by birds and squirrels, are dis- 
seminated too slowly and irregularly to enal)le such species to 
compete successfully witli pine in stocking nearby open lands. Un- 
der these conditions, pine usually follows oak. 

On the other hand, pine is unable to establish itself beneath 
dense shade, whether of pine or of hardAvoods. For this reason 
3'Oung pine growth is seldom found under the trees except in older 
open pine stands. The seeds of hardwoods, however, are dropped 
from year to year in such stands and germinate; and the seedlings, 
through their persistency and ability to endure shade, Avill survive 
in shade in which a young pine can not live, although their growth 
in this case is extremely slow. When the large pines are cut, these 
stunted hardwoods, responding to improved conditions of light and 
root space, grow rapidly and if they are numerous they form the 
larger part of the growth which follows the pine. 

in those portions of the State in which it occurs, scrub pine 
affects the permanence of the shortleaf pine stand on medium soils 
even UKjre than do the hardwoods. Scrub pine seeds ])rolifically, 
when much j^ounger and smaller than siiortleaf pine, and the seed- 
lings are tolerant of far more shade than those of the shortleaf. 
For these reasons, it not only excludes the shortleaf from old 
fields Avhich are in process of stocking, but it successfully competes 
Avith the young hardwoods in occu])ying openings in stands ot 
shortleaf pine in wliich the coAcr is too heavy for shortleaf seed- 
lings to exist, and thus in part succeeds the shortleaf in shortleaf 
stands. 

By reason of this aggressiveness, scrub pine is so completely 
replacing shortleaf pine over large areas in the northeastern paii 
of the State and near the Blue Ridge that the economic range of 
shortleaf pine is being restricted. 



12 SHORTLEAF PINE IN VIRGINIA 

MANAGEMENT 

Forest managenient as applied to old-field stands may be sum- 
marized as the use of any methods of restocking, cutting, or thin- 
ning which will reduce the cost of growing timber or add to the 
value of the timber grown. 

Natural stands are usually either understocked, at least in 
certain phases or during certain periods of growth, or else over- 
crowded. 

The maximum growth is obtained by maintaining such a num- 
ber of trees to the acre as will utilize the full capacity of the soil 
and at the same time secure the best development of the individual 
trees. Understocked stands do not use the full capacity of the soil 
and must be filled out to the required density by planting in the 
thin places. In crowded stands, on the other hand, the indi- 
vidual trees are retarded; they must be thinned in order to make 
them grow at their best rate. These requirements of the stand 
are discussed in conne-ction with the subjects of thinnings and 
planting. 

Another phase of management is cutting at the period of ma- 
turity as determined by either maximum yield or value. The rate 
of growth or accretion of a stand is not the same at all ages. The 
yearly growth rapidly increases from nearly nothing to a maxi- 
mum, then slowly declines. When the rate of annual growth be- 
gins to decline, a loss in yield is entailed if cutting is deferred. 
The time at which the maximum of the average annual yield is 
obtained varies with the size of the timber which is desired; it 
would not be the same for lumber, which requires large timber, as 
for cordwood, for w-hich small timber can be used. But while it is 
desirable to obtain the maximum annual yield from a stand, the 
cost of production is a factor Avhich cannot be neglected. 

The cost of production embraces the interest on the investment, 
the taxes, superintendence, protection, and the making of improA^e- 
ment cuttings and thinnings. As far as the needs of ow^ners and 
the market conditions allow, a stand should be cut at financial 
maturity, that is, when it yields the best, returns on the investment. 
These phases of management are considered in connection with 
yields of stands at different ages, and with the cost of growing 
timber. One of the most important considerations in manage- 
ment is the method employed for obtaining a prompt renew\al of 
the stand in order to prevent the loss of interest on the investment 
by the idleness of the land. 



SHORTLEAF PINE IN VIRGINIA 13 

Protection of stands from fire, from insects, and from fiin^is 
diseases is necessary to insure fully stocked stands and sound 
timber. 

The figures relating to the gi'owth and yield of shortleaf pine 
are based on stands which are growing on soil formerly covered 
with forests of shortleaf pine mixed with white oak, southern red 
oak (Querc'us digit ata)^ black oak, and white hickoiy. The rate 
of growth on such sites is regarded as the average or tusual rate. 
Where the pine now grows on soils which were formerly covered with 
forests of shortleaf pine mixed with post oak, with black-jack oak, 
or with Spanish oak {Quercus coecinea), or with a large propor- 
tion of these oaks together with other oaks, the rate of growth and 
the yield of the stands will be considerably lower than that given. 

Fully Stocked and Crowded^ Stands 

A stand is fully stocked when it contains all the well-grown, 
vigorous trees which the soil can support. This number decreases 
with the age of the stand and tlie consequent increase in the size 
of the trees. In a natural twenty-year-old stand of shortleaf pine 
the number to the acre should exceed 1,500; at forty years it has 
decreased to about 750; at sixty years it has fallen to less than 450. 
This reduction of the number of trees in a stand progi-esses nat- 
urally. As the trees become older and larger, their crowns spread 
and their roots extend m search of food and moisture. Com]:)eti- 
tioii for light, food and moisture ensues, and this in turn results in 
the dying of the smaller and weaker trees, which are overtopped 
and crowded out by the more vigorous ones. 

A fully-stocked stand, in which natural thinning is taking place 
rapidly, is crowded (plates I, II and IV). At any age the fact 
that a stand is crow^ded is indicated by a close crown cover and the 
presence of many dead trees and slender live trees with narrow 
crowns. In a young stand of this character less than thirty-five 
years old the crowding is so great that the crown of each tree al- 
most touches the crowns of its neighbors and direct sunlight hardly 
reaches the soil. The shade is sufficient to prevent the start of 
young trees and most shrubs beneath the pines and the carpet of 
pine needles is so thick as to exclude grass, while small dead trees 
are numerous. In stands more than thirty-five or forty years old 
there is a wider distance between adjacent crowns, due to the rapid 
dying of the larger of the slender narrow-crowned trees. This 
opening of the stand admits more sunlight, and young oaks, hick- 



14 SHORTKEAF PINE IN VIRGINIA 

ories, and other trees, as well as many shrubs, begin to gi-ow be- 
neath the pines. Dead trees and live trees with naiTow crowns are 
not so numerous as in younger stands. The mat of pine needles is 
thinner in the older stands and grass is able to spring up. 

A fully-stocked young stand of shortleaf pine has, therefore, 
a dense crown cover. In both young and old stands, if they are 
fully stocked, there are slender trees with narrow, spry crowns and 
aead trees which have been crowded out, though the latter are mcjre 
abundant in the young stands. Whether a stand is crowded and in 
need of thinning may be determined by the greater or lass abund- 
ance of crowded and dead trees, considered in connection with the 
age of the stand and the normal density of the crown canopy at a 
given age. 

Understocked Stands 

The average stand of shortleaf pine in middle and Piedmont 
Virginia, however, instead of being too densely stocked, is too 
thinly stocked. When the crowns do not interfere, or are round- 
topped with practically horizontal lower branches, the stand is to'o 
open for best gi-owth. 

Young and even middle-aged stands are frequently open, but 
their wide-spreading crowns eventually close and form a dense 
crown cover like that of a fully-stocked stand. But in this case 
dead trees and slender overtopped trees are absent : the crowns of 
the trees are too round and wnde-spreading; the stems are too short 
and limby: and the number of ti-ees to the acre is much less than 
in fully-stocked stands of the same height. (Table 9). Under- 
stocked stands of this kind do not require thinning. Moderately 
understocked young stands usually become crowded early enough 
to reduce some of the evils of understocking, but the stems of 
the trees are never so tall and free from limbs and Imots as those 
which develop when there is crowding all through the life of the 
stand and their total yield is usually less than that of a fully- 
stocked stand. (Plate III). Young understocked stands should 
be filled out by planting. 

In nearly every stand, however, there will be found at least 
groups of trees which will be benefited by thinning. The presence 
in the stand of numerous small dead trees and slender trees with 
spiry crowns is a clear indication that thinning is needed. 



SHOKTLEAF PINE IN VIK(JINIA l6 

THINNINGS 

The objects of thinnings are, first, to accelerate the gi'owth and 
shorten the time necessary to bring the stand to maturity, and, 
second, by removing defective trees ft) produce a mature stand 
formed of perfect specimens and so increase the yiekl of kiinber. 
The elimination of the weaker specimens by natural process takes 
place too slowly for the best development, because the growth of 
the trees which are ultimately to survive is retarded by the pro- 
longation of the struggle for light and food. Yet limited crowd- 
ing is necesvsaiy at certain periods to force height growth and to 
develop long, straight stems, reasonably free from limbs. More- 
over, the number of trees to the acre largely determines the volume 
of the yield and has an important bearing on the value of the 
trees. Usually the crowded stands produce the greatest volume of 
w(M)d at all ages; but when the size or diameter of th<' individual 
trees is of primary importance, as in the prodiu-tion of saw logs, 
less crowding is desirable. By means of judicious periodic thin- 
nings, it is possible both to favor competition and to relieve over- 
crowding and in this way gi-eatly to accelerate the growth of the 
remaining trees. Such thinnings reduce the number of trees, but 
they produce equally tall trees of much larger diameter, with 
straight, clean stems and but little taper. It is commonly held 
that if the larger trees are removed as they come to merchantable 
size the smaller trees will make accelerated growth. This is un- 
questionably true of many species and it is true also of short- 
leaf pine under thirty years old, but in pure old stands of short- 
leaf pine in Virginia the crowded and suppressed trees recuperate 
so slowly that it is not profitable to thin the stands in this way 
after they have passed the age of thirty-five, years. 

Classes of Trees 

Before thinnings can be intelligently made, the classes of 
trees iii a stand must be known and their relation to the growth 
of the stand understood. The live trees in a second-growth pine 
stand can be separated easily into three classes: 

DominaM Trees.— "TliQ^Q are the tallest and thriftiest speci- 
mens with the largest crowns. Their growth is rapid, both in 
height and in diameter. 

Intermediate Trees. — These are the slender, clean-bodied trees, 
with narrow, compressed crowns which are nearly as tall as the 



Iti SHORl-LEAF PINE IN VIRGINIA 

dominant trees. Their height growth is rapid, but, on account 
of their small crowns, their diameter growth is slow. Besides be- 
ing unable to make good volume growth themselves, they retard 
the growth of the dominant trees. 

Suppressed Trees. — These have fallen behind in height and 
are so much lower than the other trees that direct sunlight is 
largely excluded from them. They interfere very little with the 
growth of the larger trees. 

When overshadowing and suppression pass a certain point 
the trees die. Three-fourths of the dead trees are in the sup- 
pressed class, but intermediate trees also die from overcrowding. 
Dead trees exert no influence upon the growth of the stand. When 
possible, however, they should be removed, since they contribute 
to the danger of disease, insects, and fire. 

HOW HEAVILY TO THIN 

Thinnings must be heavy enough to provide more light and 
crown space, and more root space and soil moisture for the trees 
that are left, yet they must never be heavy enough at one time to 
admit too much sunlight and cause the crowns to spread unduly, 
with a sacrifice in the rate of height growth. Too heavy a thin- 
ning results in temporary understocking and produces the oppo- 
site of the result desired. 

To be most effective, thinnings should begin when a stand is 
twenty years old, and should be light and frequent. Early thin- 
nings prevent the crowns from crowding before their s\anmetry 
is destroyed, and yet maintain sufficient crown rivalry to secure 
continuous height growth and promote the rapid shedding of the 
lower limbs. Before removing any tree, it is necessary to con- 
sider how its removal will affect the remaining trees, not only un- 
til the next thinning, but until the stand is mature and the trees 
are merchantable. 

Thinnings should be made not less often than once every ten 
years. Even with ten-year intervals cuttings have to be too 
heavy for the best interest of the stand and excessive crowding 
takes place before a thinning is repeated. An interval of five 
years is recommended as the most desirable. This develops the 
full value of the stand, and also allow^s the cutting of enough 
cord wood from the thinnings to pay for the work. A careful 
observer will be able to lengthen the interval if the cost of thin- 
nings requires it. 



^1- 



-■\. 





'^'''-^iil 




J^^^L- 



Pl.ATE 111. 
Understocked large pole stand of shortleaf pine 80 years old. Tte trees are 
short-bodied and knotty and will yield only low grade lumber. The best that can 
be done with such a stand is to cut It, leaving slender, clean-bodied trees for seed 
trees. 



SHORTLEAF PINE IN VIKOINIA 17 

WHAT TO REMOVE IX THINNING 

Thinnings should remove such suppressed trees as are not 
necessary to complete the crown cover, since they have made their 
growth and exert little or no influence on the growth of the large 
trees. Species of lower value, like gums, post oak, maple, sassa- 
fras, and scrub pine, should also be cut, unless they are needed to 
keep the crown cover complete. Funky or diseased trees should 
be removed from stands of all ages. Short-bodied, crooked, 
loiotty, forked, or otherwise defective pine trees should be cut 
from younger stands, but should be left in old stands when their 
removal would make openings wdiich would not be filled by the 
spread of the surrounding crowns. Enough of the intermediate 
class should be removed to provide growing space for the trees 
that are left. The trees which are removed should l)e selected 
evenly through the stand. If several adjoining trees are removed, 
an opening is left w^hich will be too long in closing. If trees are 
left in groups, excessive crowding in the interior of the groups 
will follow, and this will result in the loss by shading of the in- 
terior branches and unsymmetrical development of the trees. Wlien 
there is a choice the trees which nre left for permanent growth 
should have well-developed and symmetrical croAvns. 

ACCELERATION IN GROWTH FROM THINNING 

Until they are thirty or even thirty-five years old, the inter- 
mediate as well as the dominant trees of shortleaf pine stands re- 
spond vigorously and rapidly to thinnings by accelerated growth. 
In older stands, the recuperative power of the intermediate trees 
declines and the recovery from the effects of overcrowding is slow. 
The recuperative power of the dominant class, however, is main- 
tained until the trees are sixty years old, when the period of rapid 
height growth is well past and crown isolation has taken place. 
The ability of the intermediate trees m young stands to recover 
rapidly from the effects of close crowding, permits the cutting of 
the largest trees in such stands and the leaving of the slender, 
clear-stemmed intermediate trees to form the mature stand. 

In Plate VI, fig. 1, which shows the cross section of a stem 
of shortleaf pine, is to be seen the results of accelerated and sus- 
tained growth which are due to repeated light thinnings. The 
crowded condition of the inner rings of growth show that the tree 
was a slender, intermediate tree before its crown was freed by the 



-j^g SHORTLEAF PINE IN VIRGINIA 

original thinning, made, as shown by the number of wide rings, 
forty-seven years before the tree was cut. Several thinnings, made 
since the original thinning, have prevented any marked decline in 
the comparatively rapid rate of growth which took place after the 
crown of the tree was originally freed of overcrowding. The rate 
of growth is one inch of radius every eleven years, or about one 
inch in diameter every five years '(the bark thickening as well as 
the wood),— an excellent average rate of gi'owth to seek to main- 
tain in the trees of a stand. It produces timber suitable for the 
highest classes of uses. 

METHOD OF THINNING 

The several thinnings are for the benefit of the final cutting 
and unless the thinnings are made at a profit, the yield of the 
hnal cutting must be far heavier as a result of the thinnings m 
order to make them worth while. In young stands then, it is 
possible to distribute a portion of the thinnings m the dominam 
class; in old stands, thinnings must be largely restricted to the 
suppressed and intermediate classes. Stands more than twenty 
years old, which have never been thinned, require heavier thin- 
nings than stands of the same age which have been thinned pre- 
viously. ■ 

SapUng Stands {Younf/er than Ttceni/ Years).— Thummg^ ot 
sapling stands are seldom possible on account of the expense of 
making them and the small amount and poor character of the 
wood obtained. Under average conditions of growth, the wood 
which could be cut in a thinning in such a young stand would 
be from two to four inches in diameter and would make only a 
poor quality of fuel. Thinnings at this age are not recommended 
unless the wood can be used. (Plate II). 

Small Pole Stands {From Tioenty to Thirty Years Old).— A 
crowded stand twenty-five years old contains a number of large 
trees eight or nine inches in diameter breasthigh, and a few even 
ten inches; many of which are in the advance growth, two or more 
years older than the average age of the stand. Such trees are fre- 
quently bushy and very limby, with wide-spreading crowns. Usu- 
ally ail of the nine and ten-inch trees in such a stand and many of 
the eight-inch trees can be cut. These will furnish a small quan- 
tity of saw timber. In addition to the large trees, all of the trees 
below four inches, and usually about one-half of the five-inch trees 
can be removed. If no previous thinning has been made, about 



SIIORTLEAF PINE IN VIRGINIA 19 

200 trees five inches and larger could be cut to the acre. These 
should yield about ten cords of wood, of which the material above 
nine inches might be sawed into about 500 board feet of lumber. 
About 900 trees should be left to the acre. A thinning in a twenty- 
year-old stand should yield much less, and one in a stand more 
tnan twenty-five years old should yield more and leave fewer trees 
per acre. At these ages trees are making very rapid growth, and 
the branches of the crowns are sharpiy ascending, so that com- 
paratively large openings are more quickly covered than in older 
stands. For this reason thinnings at this period present no seri- 
our difficulties, hut it is desirable even in making a thinning at 
this age to have in view the trees which are to form the final 
stand and these should be the tree with very slender and clean 
stems, that will yield several logs, and from which lumber can be 
sawed free or nearly free from any except small knots. For the 
relative value of these trees compared %ith the larger dominant 
trees in a stand, see table 16. {Plate I). 

Large Pole Stands {From Thirty to Forty Years Old).— AW 
trees below six inches, most of the six-inch trees, and some of the 
seven and eight-inch trees, should be removed from a normal 
thirty-five-year-old stand. If no previous thinning has been made, 
not less than 200 trees could be cut, many of which would, how- 
e\'er, be five inches or less in diameter. If a thinning has previ- 
ously been made, there would be fewer trees to come out. A first 
thinning at this time should yield from fourteen to seventeen 
cords to the acre. Fewer trees are removed than in thinnings in 
y( unger stands, and greater judgment must be used in making 
selections. The method of cutting in strips can be economically 
used only by farmers who either do their own logging or who can 
])ersonally superintend it. (Plate IV). 

Mature Stands {From Forty to Fifty Years Old). — If a stand 
of this age has been previously thinned, about ninety trees to the 
acre would be available for removal, comprising a few six-inch 
trees which could not have been removed earlier without making 
undue openings in the crown cover, many seven-inch and eight- 
inch trees, and some nine-inch trees. If it were a crowded stand, 
not previously thinned, from 100 to 200 trees to the acre might be 
taken out, with a yield of not less than ten cords of wood per 
acre. However, unless the stumpage value of trees from fourteen 
to sixteen inches in diameter is greater than that of trees from 
twelve to fourteen inches, a size which the trees reach when about 



20 



SHORTT^EAF PINE IN VIRGINIA 



forty-five years old, timber is produced at the lowest cost by cut- 
ting when the stand is about this age (see tables 12 and 17). 
Under ordinary conditions, the stand would be cut for lumber, and 
not thinned, at this period. (Plate V). 

This method of thinning crowded stands is based on the 
average crowded stand. 

Typical Stands. — Table I shows approximately the average 
number of trees of each diameter from four inches up, which were 
found in iiTegularly thinned stands growing under a\erage condi- 
tions. This table is approximately correct for the average of a 
number of stands, but any individual stand at a given age will 
probably show considerable variation from it, both in the total 
number of trees per acre and in the number of trees in each class, 
since slight diii'erences in the quality of the soil atfect the number 
of trees to the acre at any age, and the degree of thinning in- 
fluences both the number' of trees and their size. It shows, how- 
ever, the rapid elimination of the smaller trees, which are the ones 
which should be chiefly removed in the thinnings, and it will serve 
as a guide to indicate about the number of trees of each size which 
should be taken out at each thinning. The stands which have been 
grouped as thinned stands in some cases -were undoubtedly natur- 
ally thinly stocked and their density has been further affected by 
artificial thinnings. For this reason the favorable conditions of 
these stands can not be entirely ascribed to thinnings. 



TABLE 1. 

Approximate number of trees four inches and over in diameter to the acre 
in unsystemxitically thinned stands of shortleaf pine (the twenty-year- 
old stand is unthinned). 



Age of 






DIAMETKB BKKAST HIGH— INCHES 




stand 




















Years 


4 


5 


6 


7 


8 


9 


10 


11 


12 


13 


U 


15 


16 


I 
17 18 


Total 


20 


1 

600 400 


300 


50 


10 






















1,360 


25 


203 278 


228 


154 


92 


10 


5 










. . 








970 


80 


70 170 


176 


136 


106 


69 


25 


10 


1 










. 




765 


35 


2 7G 


121 


111 


118 


87 


46 


23 


9 


2 












615 


40 




8 


S4 


91 


115 


8S 


58 


37 


20 


8 


1 










505 


45 






28 


63 


97 


74 


64 


46 


30 


13 


4 


1 








420 


50 






6 


34 


70 


63 


63 


50 


37 


21 


9 


2 








355 


55 








12 


34 


48 


53 


52 


41 


26 


15 


7 


1 






289 


60 








2 


18 


33 


42 


42 


42 


33 


21 


12 


5 






250 


65 










10 


17 


30 


36 


3H 


35 


26 


16 


9 


3 




218 


70 








• • 


^ 


11 


21 


27 


31 


32 


28 


20 


14 


7 


1 


195 



SHORTLEAF PINE IN VIRGINIA 



21 



Table 2 shows for two stands about forty-five years old the 
ettect of thinning in increased board yield and in the distribu- 
tion of diameter classes. One is a crowded stand which has never 
been thinned; the other has been thinned for fifteen years in a 
desultory manner. Had the thinnings been systematically made, 
better results would have followed. The large number of trees 
between ten and fifteen inches in diameter in the thinned stand is 
noteworthy. 

TABLE 2. 

Effect of thinning on hoardrfoot yield of shortleaf pine and the distrihu- 
tion of diameter classes {two stands about forty-five years old). 



Diameter of Trees Breast high 



Number of Trees of Each 
Diameter to the Acre 



Unthinned 
stand 



Thinned 
stand 



5 

6 

7 

8 

9 
10-12 
13-15 

Total live trees 

Dead trees (all diameters) 

Yield in board feet from trees 9 inches and 

over in diameter 

Cords of stem wood with bark to the acre . . . 



16 


8 


52 


10 


163 


32 


124 


38 


112 


;;2 


84 


74 


5H 


132 


8 


18 


620 


344 


176 


16 


12,740 


18,770 


61 


50 



Table 3 shows the average height of the trees in stands at 
different ages, and the average diameter of all trees in unthinned 
and irregularlv thinned stands : 



22 



SHORTLEAF PINE IX VIRGINIA 



TABLE 3. 

Average height and average diameter of all trees in fully-stocked stands of 
shortleaf pine. 



Age of stand 
Years 



Avprage Height of 

Merchantable 

stand 



Avebagh; Diameter of all Trees 



Unthlnned crowded 
stands 
Inches 



Thinned stands 



20 


32 


4.0 


4.0 


25 


87 


4.8 


5.3 


30 


42 


5.5 


6.4 


35 


47 


6.2 


7.3 


40 


61 


6.7 


8.2 


45 


55 


7.3 


8.9 


50 


68 


7.7 


9.6 


55 


61 


8.1 


10.1 


60 


63 


8.5 


10.7 



Table 4 shows the number of trees nine inches and over in 
diameter breast high in unthinned and irregularly thinned stands, 
and the average diameter of such trees. 



TABLE 4. 

Average diameter and number of trees nine inches and over in fully-stocked 
thinned and unthinned stands of shortleaf pine of different ages. 



Crowded Unthinned Stands 



Age of 
stand 



Number of 

Trees per 

Acre 



Average 

Diameter of 

Trees 



Thinned Stands 



Number of 

Trees per 

Acre 



Average 

Diameter of 

Trees 



20 










25 


1 


0.1 


16 


9.3 


30 


7 


9.8 


105 


9.6 


35 


47 


95 


167 


10.0 


40 


88 


96 


207 


10.4 


45 


125 


98 


232 


10.8 


50 


156 


9.9 


245 


11 I 


56 


182 


10.1 


243 


114 


60 


200 


10.3 


230 


11.7 


65 


213 


10.5 


208 


12 


70 


210 


10.7 


192 


12.8 



SIIORTLEAF PINE IN VIRGINIA 



23 



PRODUCTIOX OF COTU)W()()D FKOM THINNED AND 
UXTHINNED STANDS 

The yield of corchvood" is determined" rather by the number 
of trees than by the size of tlie individual trees. The most 
crowded stands usually yield most heavily, and the yield appre- 
cial)ly declines as the stands become more open. This has a great 
influence upon the yield of old stands, since after the thirty-fifth 
year there is practically no increase in the yield in cords of un- 
thinned stands, on account, of the rapid dying of the smaller tiees. 
For this reason, thinnings are not so profitable for the production 
of cordwood as for the production of saw timber; though the trees 
which would die are saved, and some additional gi'owth is secured. 
If regidar thinnings are made at intervals of five years, then at 
the age of forty-five years the increased yield, including the thin- 
nings, is only thirty-three per cent., as against an eighty per cent. 

TABLE 5. 

Yield of thmnecl and unthinned stands in cords — Trees three inches and 
over in diameter. 





Unthinned 

Stands 




Thinned 


Stands-Y] 


ELD OF THI 


nnings 




stand 


Voliiine 

ill 

Different 

Ages 


Volume of 
stand be 
lore eacli 
Thinning 


Number 
o f Trees 
which can 
be rem<.v - 
d in each 
Thinning 


A p p roxi- 

mate 

average 

diameter 

of Trees 

removed 


Volume of 

Trees 
removed 
in each 
Thinning 


Total of all 
previous 

ThiniiiDgs 
at any 
Cutting 
period 


Total 
of rhin- 

nlngs 

and 

Stand* 


Years 

(1» 


Cords 


Cords 


(4) 


Inches 

(5) 


Cor 

(fi) 


Cords 

(7) 


Cords 

(8) 


20 


47 


47.0 


930 


3.3 


6 I 




47.0 


25 


57 


52.0 


205 


4.5 


5.1 


6.1 


58.1 


30 


6r 


57 


150 


5.0 


5.0 


11.2 


68.2 


85 


64 


60.0 


110 


5.5 


48 


16 2 


76.2 


40 


6t 


60.0 


85 


6.0 


4.3 


210 


81.0 


45 


64 


59.0 


68 


H.5 


40 


25.3 


S4.3 


50 


63 


57 


55 


7.0 


3 6 


29 3 


86 3 


55 


61 


54.5 


45 


7.6 




:-;2.9 


87.4 



♦Columns is the sum of columns 3 and 7. 

* Unless otherwise stated, all references to cords are to standard 
cords of 128 cubic feet, and the corded wood is measured with the bark 
on. Standard cords can be converted into long cords of 160 cubic feet 
by dividing by 1.25 or by multiplying by 4-5. Either standard or long 
cords with bark can be converted into cords without bark by multiplying 
by .77, if the wood comes from trees which average less than 7 inches 
in diameter, or multiplying by .82 if the trees average a larger diameter. 



24 



SIIOKTLEAF PINE IX VIIUilNIA 



increase obtained at the same age by the thinning for lumber. 
Unless the value of cordwood increnses with the diameter of the 
wood (as it should if the wood is used for heading or stave bolts) 
no added value per cord is secured by thinnings. 

The yield in standard cords, stem wood with bark, of thinned 
and unthinned stands of shortleaf pine of ditferent ages is shown 
m Table 5. 

. Table G shows the approximate number of trees to the acre in 
crowded stands of ditferent ages, and in thinned stands. The dif- 
ference between the number of trees in an unthinned stand and 
in the same stand five years after it has been thinned indicates 
approximately the number of trees which should be removed from 
the unthinned stand. In practice, it probably would be best to 
make two or more thinnings before reducing the number of trees 
in an old. crowded stand to the number in a normal, thinned stand. 

TABLE 6. 

Approximate number of trees of shortleaf pine to the acre in crowded and 
thinned stands. 



Total Number of Tkees per Acre 





Crowded 




Number which tan be 


Age of stand 


Unthinned 




removed from a previously 




stand 




Unthinned stand 


Years 






' 


20 


1,950 


1,250 


980 


25 


1,440 


970 


675 


:-!0 


1,235 


765 


620 


35 


1,030 


615 


525 


40 


860 


505 


440 


45 


710 


420 


355 


50 


535 


355 





Maximum, Yield of Cordwood. — The maximum yield in cords 
is obtained earlier than the maximum yield in board feet. The 
best stands more than fifty years old give no heavier yield in cords 
than younger stands, because they have few trees to the acre, 
W'hile neglected stands in which disintegregation is taking place 
show even a decline in the volume. 





^.f|; 



; i W'-- 



I- 



■t. I 






\i^' 



PLA.TE IV. 
A. crowded, large pole stand of shortleaf pine 40 years old, badly in need of 
thinning by removing the smaller pines and many of the hardwoods. Condition of 
larger trees, with long, smooth bodies, excellent. 



SHORTLEAF PINE IN VIRGINIA 



25 



TABLE 7. 

Yearly increment of shortleaf pine in cords {stem-wood and bark) of all 
trees three inches and over in diameter, hreasthigh. 



Unthinned Stands 



Thinned Stands 



Age 


Average 


Periodic Annual 


1 Average Annual 


Periodic Annual 


of 


Annual 


Increment for each 


Increment in- 


Increment for each 


stand 


Increment 


5 year Period 


cluding Thinnings 


5-year Period 


Years 


Cords 


Cords 


Cords 


Cords 


20 


2.3 




2.3 




25 


2.2 


2. 


2.3 


2.2 


30 


2.1 


]. 


2.3 


2.0 


35 


1.9 


.5 


2.2 


l.fi 


40 


1.7 


.4 


2. 


decrease 


45 


1.3 


decrease 


1.8 


" 


50 


1.2 




1.7 


" 


55 


1.1 




l.fi 


" 


60 


.8 


" 




• I 









In both thinned and unthinned stands on average sites the 
maximum yield in cords per acre is obtained by cutting between 
^he ages of twenty and twenty-five years, at whicli time a yield of 
fifty-seven cords per acre can be secured, or an average of 2.2 
cords an acre a ye-AV. The size of the wood which is obtained at 
that time is, however, much smaller than that from older stands, 
and this fact aifects its value. 



26 



SHORTLEAF PINE IN VIRGINIA 



TABLE 8. 

Cost per cord of growing shortleaf pine cordwood, stemwood with bark, in 
unthinned and thinned stands; including thinnings, land value $5.00 an 
acre, interest rate five per cent, and one per cent yearly in addition 
for taxes and protection. 













Thinned Stands 








Accumulated 


U.NTHINNKD 

STATfDS 




















^ 






Age 

of 

stand 


Cost ot Land, 
at $5 per Acre, 
6 per cent, in- 
terest, 1 p e r 
cent, added for 
taxes, less val- 
ue of land* 






Thinnings 


Net 
cost 

per 

Acre 

of 

pro- 


Final 
yield 




Final 
yield 


Cost of 
grow- 
ing per 


Amount 


Assumed 

value 

per 


Accu- 
mula- 
ted 


of 
grow- 
ing 
per 






cordt 




cord 


value! 


ducing 
Crop§ 




cord^'i 


Years 




Cords 




Cords 






Cords 




(1) 


(2) 


(3) 


(4) 


(5) 




(7) 


(8) 


(9) 


(10) 


20 


111.04 


47 


$.23 


6.1 


$ .10 




$11.04 


47 


$.23 


25 


16 46 


67 


.28 


5.1 


.15 


$ .78 


J 5 68 


62 


.30 


30 


23 72 


62 


..38 


5.0 


.20 


1.97 


21.75 


67 


.38 


35 


33.43 


64 


.52 


4.8 


.25 


3.79 


29.64 


60 


.49 


40 


46.43 


65 


.81 


4.3 


25 


6.37 


40.06 


60 


.66 


45 


63.82 


64 


.99 


4.0 


.25 


9.60 


54.33 


59 


.92 


50 


87.10 


63 


1.38 




. 


13.40 


73 70 


57 


1..30 



» Column 2 it obtained by calculating the Interest at 6 per cent, plus 1 per cent, for taxes, 
making a total of 6 per cent., compounded annually on a land value of 85 per acre. 
Since tue land will remain after the timber is sold, its value is not included in the cost 
oi growing. 

t Column 4 is obtained by dividing column 2 by column 3. 

I Column 7 Is the product of columns 5 and 6 compounded at 5 per cent every 5-year 
period. Th9 value of wood removed in thinnings (column 6) is only nominal on ac- 
count of its small size and the difficulty of making thlnnlngs- 

§ Column 8 is the remainder after deducting column 7 from column 2. 

ij Column 10 Is obtained from dividing column 8 by column 9. 

Cost of Growincf Cordirood. — Table 8 .shows tlie cost of 
growing cordwood in both thinned and nnthinned stands at a five 
per cent, interest rate. 

PKODUCTION OF SAW TIMBER 

Influence of Densif}/ of Stand Upon Yield of /Saw Timber at 
Different Ages. 

Maximum yield in himber is obtained neither from stands 
which are continuously very crowded nor from understocked stands, 
but from stands which are periodically and lightly thinned after 
having been crowded. 

The most marked eftect of thinnings in crowded stands is m 
the amount and quality of the yield in board feet. The stands 
which were measured to determine the etfects of thinnings had 
been thinned in no definite manner; in some cases only the smaller 
trees, in other cases also some of the larger ones, had been cut out, 



SHORTLEAF PINE IN VIRGINIA 



27 



as farm needs required. Some of these thinned stands were evi- 
denth' somewhat understocked; some were still too crowded; •and 
others, at the time the measurements were made, had not had time 
to respond fully to the thinnings. It is probable that by sys- 
tematic thinning<of the kind recommended the yield shown in the 
tables could be further increased ten or even twenty per cent. 

Table 9 shows the yield of stands which have dill'erent 
numbers of trees to the acre; in other words the yield is of under- 
stocked, thinned, and crowded stands. The yield is based on cut- 
ting to nine inches in diameter breasthigh, which is equivalent 
to about eleven inches on the stump. In the understocked stands 
the crown cover is practically as complete as in the thinned and 
crowded ones, but all the trees are low and short-bodied and few 
slender or dead trees are present. (Plate III). 



TABLE 9. 

Yield of stands of shortleaf pme having different numbers of trees per acre, 
(influence of density of stands upon yield of saw timber). 



AVKRAGB Understocked 
Stands 


Pdlly Stocked Stands 

WHICH HAVE BEEN THINNED 


Crowded Stands, 
Unthinnkd 


Age 
Years 


Number of 
Trees to 
the Acre 


Yield 

in Board 

Feet 


Number Of 
Trees to 
the Acre 


Yield 
In Board 

Feet 


Number of 
Trees to 
the Acre 


Yield 

in Board 

Feet 


30 
40 
60 
60 


350 
300 
150 
100 


3.800 
5,700 
6,900 
7,800 


765 

505 
355 

255 


8,400 
16.400 
20,400 
23,000 


1,235 
860 
535 
395 


200 

6.00U 

13,100 

16,800 



The yield of an understocked stand when more than thirty 
years old is only about one-half of that obtainable from a fully 
stocked stand of the same age. after thinning. Many of the trees 
in oi)en, understocked stands attain a diameter of nine or more 
inches sooner' than do trees in crowtled stands, for in crowded 
stands the continued comj)etition retards the diameter growth of 
the individual trees. This explains why crowded stands thirty 
years old are not producing merchantable timber. 

In the average understocked stand the cost of growing the 
timber is far in excess of its present stumpage price. This is 
largely due to the small yield. If sold at $2 per thousand board 
feet, timber from understocked stands pays less than two per cent, 
on the assumed investment of $5 an acre. 



28 



SHORTLEAF PINE IN VIRGINIA 



Table 10 shows the influence of density upon the cost per 
1,000 board feet of gi'owing shortleaf pine stunipage in old-field 
stands, based on net returns at five per cent., taxes one per cent, in 
addition, land value $5 an acre. 

TABLE 10. 

Influence of number of trees, or of density of stand on cost of growing 
1,000 board feet in old-field standi of shortleaf pine. 



Age 


Accumulated 

Cost of the 

Investment 

per Acre 

less the 

Value of the 

Land 


Average LTndek- 
Stocked Stands 


Crowded, Un- 
THiNNBD Stands 


Thinned Stands, Neg- 

i^KCTiNG Value of 

Thinnings 


of 
stand 

Years 


Yield Cost 
per per 
Acre M ft 

Bd. ft. 1 


Yield 
Acre 
Bd. ft. 


Cost 
M^ft. 


Yield 
per 
Acre 

Bd ft. 


Cost 
M^ft. 


80 
40 
50 
60 


1 23.72 
46.43 
87.10 
159.90 


3,800 
5,700 
6,900 
7,800 


$6.80 

8.10 

12 60 

20.51 


■ 6,000 
13,100 
15,000 


■$■7,73 
6.65 
1066 


8,400 
16,400 
20,400 
23 000 


$ 2.82 
2.88 
4.27 
6 82 



At every age if thinnings are made without loss, the cost of 
growing stumpage in fully stocked thinned stands is less than the 
cost of growing it either in crowded or understocked stands. If 
thinnings do not pay lor themselves the cost is higher, and if 
they pay a profit, the cost is lower. 

Age of Cutttng for Maxinvum, Yield. — The maximum annual 
yield in board feet from trees nine inches and over in diameter 
breasthigh is obtained from thinned stands when they are cut at 
forty-eight years of age. At that time in such a stand, the aver- 
age annual yield per acre is about 410 board feet, and the diameter 
of the average-sized tree is about 9.5 inches breasthigh, or 11.5 
inches on the stump. 

For unthmned stands, the maximum anmual yield is obtained 
by cutting when about fifty-seven 3^ears old. The average dia- 
meter of the trees in such a stand is about 8.2 inches at breast- 
height or 9.8 inches on the stump. Table 11 shows the yearly 
increment in board feet of trees nine incnes and over in diameter 
breasthigh. 



SHORTLEAF PINE IN VIRGINIA 
TABLE 11. 



29 



Annual increment per acre in board feet of trees of shortleaf pine nine 
inches and over in diameter breasthigh. 





Thinnned Stand (Thinnings 
Neglected) 


Unthinned Stand 


Age 

of 

stand 

Years 


Average 

Annual 

Increment 

Board feet 


Periodic Annual 
Incremeut for 
each Decade 

Board feet 


Average 

Annual 

Increment 

Board feet 


Periodic Annual 
Increment tor 
each Decade 

Board feet 


30 


280 
410 
408 
383 
357 








40 


800 
400 
260 
200 


150 
208 
250 
238 




50 
60 

•?o 


710 
190 
170 



Cost af Growing Saw Timber. — If only the maximum iinmial 
yield were to be considered in gi^owing timber it would undoubt- 
edly be advisable in all cases to hold timber until this could be 
secured. The cost of carrying the investment, however, is a factor 
which cannot be overlooked. The land has a sale value, and taxes 
are paid upon it yearly. In addition, the cost of protection, such 
as maintaining fences, extinguishing fires, etc., must often be borne. 

In making a calculation of the cost of growing timber it is 
necessary to determine, from the time stocking took place to the 
time when the timber is out, the accumulated taxes paid on the 
land and the interest compounded annually on the investment 
represented by the value of the land and the cost of stocking it. 
In making this calculation, both the actual and tax assessment 
value of the land has been assumed to be $5 an acre for the entire 
period of growth. The tax rate and other expenses are assumed 
to be one per cent, on this valuation. If the owner is content 
with a gross interest of six per cent, on his investment, then the 
net rate, after deducting taxes and other expenses, will be five per 
cent, a year. 

In the old-field stands there is no cost of stocking to consider. 
The profits of thinnings are supposed to be the same as those 
given in column 7, Table 8, for cordwood. 

In oi-der to obtain a six per cent, investment which, after 
allowing one per cent, per annum for taxes and protection, will 
yield five per cent, net, the following yields and prices must be 
-secured. The value of the land is placed at $5 an acre. If stump- 



30 



SHORTI^EAF PINE IX VIRGINIA 



age is sold at less than the cost of growing 1,000 board feet, or if 
the stands cut less than the amounts given at the ditterent ages, 
less than five per cent, net is obtained on the investment. If 
stumpage is sola at a higher price and the value of the land is not 
more than $5 an acre, then the investment will yield more than 
five per cent. 

TABLE 12. 

Cost of growing shortlenf pine satc-Umber in unthinned and thinned stands, 
including thinnings. Land value $5 an acre: interest rate five per 
cent; one per cent in addition alloiced for taxes. 





Unthinnkd Stand 


Thinned Stand 


Age 

of 

stand 

Years 


Accumulated Cost of In- 
vestment Land at So 
an acre, 5fp interest, Ijf 
added for taxes, less 
cost ot land 


Yield 
Bd. ft. 


Cost of 

growing 

per M 

bd. rt. 


Net Cost 

per acre 

of 

producing 

crop* 


Final 
yield 

Bd. ft. 


Cost of 

growing 

per M 

bd. ft. 


20 


$11.04 
16.46 
23.72 
33.43 
46.43 
63.82 
87.10 






$11.04 
15.68 
21.75 
29.64 
40.('6 
54.33 
73.70 


' 900 
8,400 
13.400 
16,400 
18,700 
20,400 




25 






117.00 
2.59 
2.21 
2.44 
2.90 
3.61 


30 
85 
40 
45 
50 


200 

1,400 

6 000 

10,200 

13,106 


■ 123.80 ■ 
7.64 
6 25 
6.70 



* After deducting value of thinnings as shown in Table 8. 

The cheapest cost of production, wdth interest at five per cent. 
and taxes at one per cent., or six per cent, for both is $6.25 a 
thousand board feet from unthinned .stands and $2.21 from thinned 
stands. 

The period when the cost of growing the timber is the lowest 
is known as the financial maPurity. If timber' is held longer than 
the period of financial maturity, there must be a considerable ad- 
vance in its value to cover the cost of carrying it, that is, the 
accumulated interest and taxes, and this is particularly true of 
old stands the volume of which is increasing very slowly or ])er- 
haps actually declining. 

The owner of timberland is interested in knowing the rate of 
interest he may expect from his investment when the product sells 
at a give price. Tables 13 and 14 show the interest yielded 
by stands of old-field pine at different ages, with the land 
worth $5 an acre and with stumpage selling at $2 a thou.sand 
feet and cordwood at twenty-five cents a cord. In table 14 



SHORTLEAF PINE IN VIRGINIA 



31 



for cordwood from a thinned stand, it is assumed that thinnings 
produce the ivturns alloAved in cohimn 7, Table 8. 

In the table for board feet from a thinned stand, thinnings 
are supposed to be made without either profit or loss. The inter- 
est yielded is gross, and includes taxes and the cost of protection — 
items which would usually amount to about one per cent, of the 
land value and would correspondingly reduce the returns. 

TABLE 13. 

SAW TIMBER STUMPAGE AT $2 A THOUSAND BOARD FEET. 

Oross rate per cent yielded hy stands of old-field pine on a land i>nlue of 
$5 an acre.* 



Age 

of 

stand 



Thinned Stand 



Value of stand 
neglecting 
Thinnings 



Gross rate 

per cent. 

Yielded on 

Land Value 

Per cent. 



Unthinned Stand 



Yield 
per 
Acre 



Value 

of 
stand 



Gross rate 

per cent. 

Yielded 

on Laud 

Value 

Pet cent. 



30 


8,-100 
13,400 
16,400 
18,700 
20,400 


• $16.80 
26.80 
32.80 
37.40 
40.80 


4.3 
50 
50 
4.5 

4.0 








35 

40 
45 
50 


' 6,000 
10,200 
13,100 


$12.00 
20.40 
26.20 


■ 2.5 
.3.2 
3.8 



TABLE 14. 

CORDWOOD STUMPAGE OF FINAL YIELD AT 25 CENTS A CORD. 

Gross rate per cent yielded by stands of shortleaf pine in old-field ivith a 
land value of $5 an acre* 





Thinned Stand 


—Unthinned Stand 


Age 

of 

stand 

Years 


Final 
yield 

Cords 


Total Value, per 
Acre, including Ac- 
cumulated Value 
of Thinnings at i% 
compound interest 


Gross rate 

per cent, 

Yielded on 

Land Value 

Per cent. 


Yield 
per 
Acre 

Cords 


Value 

of 
stand 


Gross rate 

.ver cent. 

Yielded on 

Land Value 

Per cent. 


20 


47 
52 
57 
60 
(iO 
59 
57 






4!) 
57 
62 
64 
65 
64 
63 


$11.75 
14 25 
15.50 
16.00 
16.25 
16.00 
15.75 


4 3 


25 
30 
35 
40 
45 
50 


118.74 

16.08 
18.44 
19.65 
23.94 
26.43 


4.0 
4.0 
3.8 
3.6 
3,5 
3.2 


4.2 
3.8 
3.5 
3.0 
28 
2.5 



Gross rate per cent, includes taxes and cost of protection as well as the interest on 
the Investment. 



32 



SHORTLEAF PINE IN VIRGINIA 



VALUE OF TREES AND STANDS 

The lumber from second-growth stands of shortleaf pine, 
when . awed into boards one inch thick and graded according to 
the rules of the North Carolina Pine Association, sells for a high- 
er price than if it is sold ungraded, 9r than if it is sold in the 
form of framing. The lumber which is sawed from young stands 
less than 35 years old is as a rule too narrow, and that from stands 
in which the trees have not been crowded, is too knotty to justify 
grading. TIiq older the stand the more valuable becomes the lum- 
ber which can be cut from it not only on account of greater widths 
but also a larger proportion of the high grade^. If the trees of 
ditt'erent diameters in a crowded stand which is about 50 years old 
(the age of maturity) are carefully sawed into boards of even 
width and uniform thickness, they will yield approximately the 
amounts of the different grades of lumber which are given in 
Table 15, The figures in this table are based on actual measure- 
ments of grades which were made at a mill where trees of these 
sizes and age were being cut. 



TABLE 15. 

Total volumes m bo'ird feet, and the amount of the f/rar/e.s- of luinher in trees of different 
diameters and heights in dense stands of short- leaf pine 4o to 60 years old. 











AMOUNT.S OF THB 


OlFFEKKNT 




Diameter 


Total 

height 

Feet 


Number 

of in foot 

logs 


Diameter 
Inside 
bark at 
the top 
Inches 


Grades S 


AWED From Trees 


Total 
volume 


breast- 
high 
Inches 


No. I. 


No. 2. 
B o 


No. 3. 
a r d 


Box or 

frm'g 
F e 


other 

grades 

e t 


1-4 inch 
^aw kerf 
Bd. ft. 


7 


48 


li 


5.0 






4 


12 


6 


22 


8 


m 


n 


6.0 




2 


6 


14 


6 


28 


9 


57 


2 


6.5 




4 


13 


15 


6 


38 


10 


62 


n 


6.5 


4 


8 


18 


19 


6 


55 


11 


66 


2h 


6.5 


8 


12 


25 


28 


6 


79 


13 


70 


3 


7.0 


18 


23 


27 


35 


6 


l09 


13 


75 


3 


7.0 


26 ' 33 


37 


40 


6 


142 


14 


78 


3 


7.5 


32 1 38 


48 


56 


7 


J8I 


15 


SO 


3i 


7.5 


47 


40 


63 


67 


9 


228 


16 


80 


H 


8.0 


70 


48 


75 


/»i 


u 


280 


17 


80 


3^ 


8.0 


74 


60 


104 


87 


13 


388 


18 


81 


H 


8.0 


83 


76 


120 


103 


16 


398 


19 


81 


^ 


8.5 


92 


92 


143 


115. 


18 


460 


20 


81 


3i 


90 


105 


115 


167 


122 


18 


527 


21 


81 


3i 


9.0 


120 


133 


197 


125 


18 


598 


22 


81 


3^ 


9.0 


136 


163 


230 


129 


20 


678 



The smaller trees in stands of this age are long-bodied and 
clear stemmed, have very little taper and thin bark, and, although 




Mature stand of sliortleaf pine. Trees nearly uniform in size and ready 
be cut for lumber. Groups of slender, wlndrtrm trees can be left for seed trees. 



SHOnXLEAl I'JXK FN VIR(;TNT.\ 



33 



the boards which can be sawed from such trees are narrow, they 
are comparatively free from knots and will justify grading if 
handled in connection with the wider boai-ds from the larger trees. 
Trees of the same size in younger stands are more tapering and 
more knotty, and the lumber is of lower grade. 

Air-dried lumber of the ditl'erent grades, consisting of mix- 
ed width, but less than 12 inches wide, is quoted (November, 1912) 
at the following prices per 1,000 board feet, delivered at Norfolk, 
Eichmond, Petersburg, Lynchburg, and Eoanoke: No. 1, $26; 
No. 2, $24; No. 3, $20; Box, $18; Red heart and cull, $16; Bark 
strip, Nos. 1 & 2, $20: Bark strip, box $12. In Table 16 these 
values have been applied to the amount of ditl'erent diameters 
delivered at Norfolk and the other points named above. 

TABLE 16. 

Value delivered at Norfolk, Rk-hmond, Petersburg Roanoke, and Lynchburg, of the 
graded lumber cut from trees of differerd diameters and heights* growing in crowded 
second-growth stands 45 to GO yearn old and the value of single trees and their stump- 
age per 1,000 board feet under different costs of sawing and delivery at ihtse points. 





Value of 1 


umber de- 


Stumpage v 


alue per tree w 


ith expenses 




livered at Norfolk, Kich- 


of sawing and delivery per' 


Diameter 


mond, etc. 


1,000 board ft. at 


breast-high 














From each 
tree 


Per 1,000 
board ft. 


$10 


U2 


$14 


7 


$ .35 


$16 95 


$ .13 t 


$ .08 - 


$ .40 


S 


.47 


16.40 


.18 .12 


.06 


9 


.66 


17.40 


.28 1 .21 


.13 


10 


1.01 


1 8 35 


.46 ! .35 


.24 


11 


1 58 


19.30 


.74 .58 


.42 


12 


2.16 


19.80 


1 .06 1 .85 


.63 


13 


2.86 


20.15 . 


1.44 1.16 


.87 


14 


3.79 


20.95 


1.98 1 1.62 


1.26 


15 


4.75 


21.40 


2.58 I 2.12 


1.67 


If) 


6.30 


22.50 


3.58 3.02 


2.46 


17 


7.60 


22.55 


4.23 3.56 


2.89 


18 


8.95 


22 50 


4 79 1 4.18 


3.38 


19 


10.40 


22.45 


5.73 4.81 


3.89 


20 


11.80 


22.40 


6.53 I 5 48 


4.42 . 


21 


13.40 


22.40 


7.41 j 6.22 


5.02 


22 


15.17 


22.35 


8.37 


601 


5.65 



*Heighti which are given in table 15. 

tObtained by deductingthecost ofsawing and delivery per 1,000 board feet from the de- 
liverel value per 1,000 board feet, reducing the rtmaindSr to the value of one board foot 
and multiplying by the number of board feet per tree as shown In table 15: thus, $15.95 
less SIOOO equal to .$6.95— ?5.i)o divided by IOjO and multiplied by 22 Is equal to S.13. 



In table 15 the expenses of saAving and delivery, $10; $12; 
and $14 per 1,000 board feet are supposed to represent a low, 



34 



SHORTLEAF IMXE IX VIR(;IMA 



a medium, and a high fo^,t of operation, and are made up of the 
cost of logging, felling, sawing, grading, interest on the investment 
and carrying charges, cost of selling, delivery at market and load- 
ing, drying, and profit of the operator. A profit of from $2 to $3 
a thousand feet should be allowed in portable mill operations, 
the profit varying according to the size and length of the oper- 
ation. It is noteworthy that while the value of the lumber per 
1.000 board feet which is yielded by trees of dilferent diameters 
increases rapidly up to IG inches in diameter, there is a decline 
in the value per 1,000 feet of the lumber which is sawed from 
trees of diameter above IT inches. This is due to the fact that the 
largest trees in these stands have larger and more numerous knots 
in their stems and yield a lower proportion of the high grades 
of lumber than do the slender, more clean stemmed, intermediate, 
and suppressed trees. 

If the number of trees of each diameter per acre in a 45- 
year old stand (see Table '2) be multiplied by the value per tree 
of each respective diameter, the sum of these amounts will give 
the total value of the stand per acre, and from this the value per 
1.000 feet of the stand. A similar set of values can be determined 
for trees in younger and ohler stands. These are given in Table IT. 

TABLE 17. 



Value per 1,000 hoard feet of the lumber which can he sawed from dense unthinned stands 
of short-leaf pine nnder different costs of manufcmLure and delivery. 



Age of stand 
years 



Value per 1,000 board feet under a 
ofoperailon and delivery of 


cost 


$10 


m 


114 


$ 5.40 
6.00 
7.05 
8.60 
10.05 


4.00 
5 05 
6.60 
8 05 




$ 1 40 
2.00 
3.05 
4.40 
6.05 



If the values in Table IT are compared with the cost per 
1,000 board feet of growing timber, shown in Table 10, it will 
be seen that the investment, if the stand is unthinned. does not 
yield five per cent. net. except under a logging cost of $10 and 
when the stand is cut at the age of 50 years. 

In a regularly thinned stand from Avhich the very knotty trees 
have been systematically removed when the stand was young. 



SHOI{TLf:AF PrXE IX VTR(;IXIA 



:^r, 



Jeaving only the longest-bodied and clearest stemmed trees at 
each cutting and in which the trees have been forced to large 
diameters by isolation after the clear stemdeiigth is 50 feet in 
length, it is believed that the stiimpage value can be forced to a 
value of $8 a 1.000 feet under a logging cost of $12 wIhmi 50 
years old. This would yield about $250 per acre. 

WASTE IX C'UTTIXt; SMALL TIJEES 

The following table shows the actual volume in board feet of 
trees of dilferent diameters anil heights when cut with a saw taking 
a kerf of one-fourth inch ; the volume in board feet when scaletl 
by Doyle-Scribner log rule; the volume of stem, wood only, in cubic 
feet: the number of boaixl feet. Doyle-Scribner rule, per cubic foot 
of volume; and the i)erccntage of waste. 

TABLE 18.. 

Volinnc in hoard feet and in cubic feet and. per cent of icaste in sawing 
trees of shortleaf pine of different diameters. 



Diame- 
ter 
Breast- 
high 



Total 
Height 



Actual 

Volume 

1^ inch 

Saw Kerf 



Volume 

as scaled 

b\ Doyles 

Scribner 

rule 



Hoard feet Board feet 



'>•) 


s 


28 


Hi 


.'58 


25 


55 


8s 


79 


56 


109 


SO 


112 


111 


181 


l:U 


'226 


170 



Volume 
of Stem 

Wood 

only 

Cubic 
feet 



Actual number 
of Board feet, 
per Cubic foot 



Per cent, 
of waste In 

Stump, 
Tv.ps, Slabs 

and Kerf 



3. 


75 


H 


75 


;>. 


75 


.S.3 


72 


4. 


m 


4.5 


62 


4.9 


59 


5. 


58 


5. 


58 



The loss in scaling by Doyle-Scriber rule exceeds seventy-five 
per cent, of the total cul)ic volume of the stem until the tree reaches 
a diameter of thirteen inches, breasthigh. This large proportion 
of wa.ste is an excellent reason for not cutting young stands for 
saw timber or for not cutting the .-mall tree.> in old stands unless 
they are suppressed trees. 



LUMBEEIXtr AXD RESTOC KIX(i 

Simultaneously with lumbering coyies the subject of securing 
-I sec(md stand of young pine to iei)lace the one which is cut. 



36 SHORTLEAP^ PINE IX VIRGINIA 

After ordinary culling, such as is practiced for farm use, or in 
clear cutting stands of pine for lumber or for fuel, hardwoods 
generally form the main part of the young stand. The reasons 
for this are explained under the heading "Permanency of Old- 
Field Pine Stands." To obtain reproduction of pine, it is neces- 
sary: (1) To cut nearly clean, that there may be abundant light: 
(2) To leave seed-bearing pine trees scattered over the area or 
standing nearby; (3) To cut out the large trees of such hard- 
woods as dogwood, post oak, hickory, persimmon, etc., which have 
sprung up beneath the pines, and Avhich would suppress many 
pine seedlings by their shade; (4) To bring as much of the min- 
eral soil to the surface as possible. The hardwoods should be cut 
in September, when their sprouting capacity is lowest. 

Two methods of cutting are suggested. One method, leaving 
isolated seed trees, is for use where the entire stand must be cut 
at one time. The other, cutting in strips, or groups, can be applied 
wdien there is a stead.y market for saw^ logs, as when there is a 
nearby permanent sawmill, or logs can be shipped to such a miH, 
and when it is possible to make two or more cuttings, not less 
than five years apart, in a stand, always having in view, hoAvever. 
the development of the valuable long-bodied and clean-stemmed 
trees (table 16) which are to form the mature stand. 

Isolated Seed Trees. — When the saw-timber must be remoA ed 
at one cutting it is advisable to prepare for the final cutting at the 
time of the last thinning by developing seed trees. At forty-five 
years of age, the production of seed by shortleaf pine is still ex- 
tremely light, particularly in dense stands. If there are no old 
forest pines which will serve for seed trees within 100 yai-ds of 
the tract, one object of the last thinning should be to select and 
develop trees for seed trees. 

Vigorous, large-croAvned trees should be selected for this pur- 
pose. They should be not less than four to the acre, and should 
be evenly distributed or else located on the tops of hills or knolls. 
Their crowns should be entirely freed by heavy thinnings on all 
sides. This should lead to the production of a heavy crop of cones 
and fertile seed within five years. If the crowns again crowd be- 
fore lumbering, they should again be freed by further thinning. 

When lumbering takes place, all merchantable trees should be 
cut except these seed trees, which should be able to produce enough 
seed in a few years to restock the land. (Plate V). If the seed 
trees are windfirm thev can i>o over until the next stand is cut: 



&7 

RIIORTLEAJ^ PINE IN VIRGINIA 



if they fall, they ca.. be used without breaking down <""""";>' "/ 
he In trees in the young stand. Since the period of rest.ct 
in. by this method would probably occupy trom four to six years. 
tU soil would not be fully used dunng this time 

Cuttinf, in S««>.-Complete and rapid stocking .. bette as 
sured by cr.tting in strips, but this method presupposes a contmu 
^rliket for saw logs. The area should be clear-cut over strip 
Z xceeding 200 feet in width, alternating with strips of equal 
r-dth whichlre only culled of the smaller trees. «" 1--^^,,^^ ^^ 
these strips should be at right angles to the roads; on '"Hy 1» d 
hy should lie up and down the slopes. The wooded strips shond 
be le-ily thinned by the removal of all except ^^ l^f-'";'- 
'diich should not exceed twenty to the acre, and should be lef 
w i isdated. These trees will serve as seed trees, and on account 
If the" large number they should seed the entire area heavily 
wit*: five to ten years. As soon as a thorough restocking i 
assured they can be cut. Some of the young trees will be bioken 
dor brtthe loss will not te serious. The diameter gi-owth ot 
the seed trees after the thinning will be large because of this isola- 
;; Blanks ten or more feet square left after the seed trees are 
cut should be planted by seed spotting as described under the di- 
re tons for planting. The two loggings will increase the danger 
from fire, requiring additional precautionary measures to be taken. 
This method can be varied by leaving the seed trees in groups. 
entti„ff Vnthmned ^«««A.-Both of the above methods pre^ 
suppose that the stand which is being cut has been thinned, and 
consequently is formed entirely or largely of trees of merchantable 

'"''ah understocked stand, similar to that shown in plate III, 
and in which the trees are largel.v of merchantable size can be 
cut so as to secure a restocking, by leaving some of the moie 
slender but well crowned trees for seed trees. 

The problem of cutting a crowded stand to the best advalUage 
and in a manner to secure a restocking is more difficult. The tiees 
n such a stand have a much greater range of diameter than thos 
in a thinned stand. There is a large number of small suppressed 
and intermediate trees which may be too small to be c« eco- 
nomically for saw timber '(see "Waste in cutting small rees" page 
35) In such a case it may be desirable to remove the stand n 
two or more cuttings, made at intervals of five or more .v«ar«- At 
the first cutting only the largest trees should be cut, particulariy 



38 SHORTLEAF PIXE IX VIR(;IXIA 

those which have short and knotty stems. Such as have very 
slender clean stems and good crowns should be left, but enough 
of the largest trees should be taken to open the crown cover one- 
third. Such a cutting might remove one-tenth of the total num- 
ber of trees but more than one-half of the saw log volume of the 
stand. At the second cutting not only should most of the trees 
which have grown to merchantable size l)e removed, but also such 
of the smaller stunted trees as have shown no indication of thrift 
since the first cutting. The trees wliich are left should be choice 
clean-stemmed specimens with medium sized, but thrifty crowns. 
They can be left at the rate of ten to twenty to the acre. Such 
trees as have weak stems which would be likely to be bowed or 
broken by wind or sleet should not be left. Thickets of high 
shrubs and broadleaf trees should be cut. It is probable that by 
the time of the second cutting groups of young seedlings, about 
one foot in height, will have api)eared beneath the openings made 
by the first cutting. Seed from the trees which are left after the 
second cutting will complete the restocking. Two courses can be 
followed in regard to the trees which are left after the second 
cutting. Either they can be removed after thorough seedling es- 
tablishment is assured, or they can be held over an-d cut at some 
thinning period of the young stand. If trees with fifty feet of 
clear length and diameters of from ten to twelve inches are left 
after the second cutting and are held until they are tAventy to 
twenty-four inches in diameter their stumpage value Avill increase 
from three to five times. This increase in value will be due en- 
tirely to the greater size of the bigs, which Avill yield a high grade 
of lumber and can be sawn with small waste. (See Tables Ifi and 
18 and Plate II, Fig. 1). 

No method of cutting a crowded unthinned stand, howcAer. 
will give as great a yield in board feet per acre, or will produce 
logs of as high a gi'ade. as can be obtained from a well-thinned 
stand. 

PLAXTINO AVASTE LAND 

On many farms in middle Virginia there are tracts of gMllied. 
or shallow soiled or rocky, or other poor or waste land which are 
either without a growth of pine or are stocking extremely sloAvly 
and irregularly. Shortleaf pine could be planted profitably on 
such tracts. The sound seed of this pine sprout so freely, and the 
growth of the young seedling is so rapid, that direct seeding can 



SIIOKTI.KAI PINE IN \IHGINIA. 



39 



be made in place of usiiio- young phuits. Seed should be planted 
in spots six feet apart in well loosened soil and lightly covered, 
not deeper than one-half inch Avith earth. One of the two follow- 
ing methods can be used. If the tract can be plowed, shallow 
furrows can be laid otl' at intervals of six feet with a shovel plow 
or small turning plow, and the seed dropped at six-foot intervals 
m the furrows and lightly covered with a weeding hoe. If a plow 
cannot be used, the earth can be loosened with a light grub hoe 
over a spot six or eight inches sijuare, and the seed planted and 
lightly covered in the middle of this spot. If the soil is either 
(b-y or light and sandy the planter should step ou the spot after 
covering to bring the earth in <'lose contact with the seed and in- 
sure germination. Set poles should be used to keep the rows 
straight. 

The seed of shortleaf piue has a low germinating percentage, 
seldom more than forty-five per cent., and a number of seed, 
twelve or fifteen, should therefore be dropped in a hole. As many 
as can easily be held between the thumb, index finger and second 
hnger will insure a stand. There are about 50,000 seed to a pound, 
so that a pound, if carefully handled, will plant an acre. The 
smallness of the seeds, however, makes them difhcult to handle, 
and an inexperienced planter will usually drop more than are 
necessary for obtaining a stand. Planting should be done at any 
time between the middle of February and the first of April, 
whenever the soil is in suitable condition. Protection from fire 
and cattle is absolutely necessary until the trees are three or four 
inches in diameter and the bark thick enough to afford reasonable 
protection, which will require from ten to fifteen years. 

Heturns from Plantations. — If such plantations are carefully 
thinned their yield should greatly exceed that of natural stands. 

rhe cost of planting au acre and of carrying the investment 
is calculated on the basis of a land value of %l() an acre, Avith five 
per cent, compound interest, which includes an allowance of one 
per cent, an acre a year for taxes and protection. This land value 
is low for soils which will produce good shortleaf pine. The prices 
at which stumpage must be sold to net four per cent, on the in- 
vestment are shown in Table 10. 

Cost of land $10 00 

Cost of seed one pound per acre 2 50 

Cost of planting per acre 1 50 

Total initial cost of investment $14 00 



40 



gHOUTLEAF PINE IN VIRGINIA. 
TABLE 19. 



cost of producim snortleaf pine stumpage in plantations with five per 
cent gross interest on investment. 




Thinnings made at middle of decades yield about eleven cords 
at twenty-five years, fifteen cords at thirty-five years, and ten 
cords at forty-five years per acre. 

The minimum cost of producing lumber would be about i^3.8-^ 
per 1,000 board feet, when a stand is about forty years old. 

The minimum cost of producing cordwood would be about 
sixty-five cents a cord at an age of thirty years 

These figures, wnich are conservative, indicate that planta- 
tions can be expected to yield at least five per cent, gross or our 
per cent, net after allowing one per cent, or ten cents an acie a 
year, for taxes and protection. With regularly made and care^ 
fullv executed thinnin-s, the yield would probably exceed that ot 
the irregularly thinned stands on which the calculations are based 
and the cost of production would be lowered; m other words a 
higher interest rate would be obtained. 

In order for a plantation to yield five per cent, net or six per 
cent, gross, allowing one per cent, an acre a year for taxes and fire 
protection, the following returns, which are fair and reasonable, 
must be obtained from stands of dilferent ages. 



SHOR'nj^AF PINE IK VIR(ilNIA. 



41 



TABLE 20. 

Cost of produciniii shortlraf pmc stumpage in plantations with six per cent 
gross interest on investment. 





w^Boa 


innings 
ladle of 
50 cents 
landing 
iiulated 
t 4 per 


ard feet 
9" and 
lameter 
h. 


4-> J, 


'O^fe 


o% 


1 




£.2 

8h 




5^- 


o 














•< 


Accui 
ofIn 
Acre 
poun 
cent 
Valu 


^liSa*^ 


l^si 


it 


«^ts 


*^s 


Years 


sap. -.5 2 


r:oSS 


l°°« 


s^ 


20 


$ 34.80 








21 


11.66 


30 


70.36 


$ 7.00 


5,8C0 


$ 10.91 


51 


1.23 


40 


184.06 


20.10 


14,800 


7.70 


60 


1.88 


50 


247.88 


40. 2S 


19,300 


10.77 


60 


3.30 



* On account of the small amount of the thinnings and the short period during which tha 
money from them would be invested only 4 per cent, net is allowed on them. 

In neitlier of the foregoing calculations is any allowance made 
for superintendence, and possible losses from insects, sleet and 
snow breakage, and windstorm damage, but it must also be re- 
membered that the constant increase in the price of timber is like- 
wise neglected. 

thp: protpxtion' op^ stands 

The two important dangers to pine stands, fire and insects, 
are in a measure interrelated. Those trees Avhich have been weak- 
ened or injured by fires invite insects, while stands which are lit- 
tered by the wood which has died from in.sect depredations, and 
which have become grassy on acconnt of openings made in the 
crown cover where trees have been killed by insects are particularly 
expo.sed to serious damage from fire. With both dangers, pre- 
vention is the most effective means of control. 

Fires. — While the danger of fire is always present, it is far 
more serious in connection with young stands and particularly 
those in jjrocess of stocking, such as fields which have recently 
been turned out, or newly cut or lumbered land. Fires injure 
such yonng stands at any season of the year in which the}' may 
occur. Although many individuals of shortleaf pine between one 
and two feet high, when killed by an early spring fire, will sprout.. 
the sprouting capacitv is irregular and unreliable (Plate VI, fig. 2). 
Moreover, most of such sprouts die in a few years, while many of 
the survivors are forked. After the tenth vear. the heavv shade of 



42 SHORTLEAF PINE IN VIRGINIA, 

croAvded stands and the thickened bark greatl}' reduce the danger 
of fire, but even the heavy bark of old trees does not afi'ord com- 
plete protection from hot spring fires when these are driven by a 
strong vpind. Thickly stocked shortleaf pine stands do not, as a 
rule, become grassy or foul with shrubs and herbage, and conse- 
quently do not require periodic winter burning for the purpose of 
protection, such as may often be necessary for pole stands and 
mature stands of loblolly and longleaf pines. Although no visible 
damage may be done to older trees by such burnings, the rate of 
growth is reduced by the destruction of the pine straw and the 
humus, while even the slight scorching of trees may lead to the 
entrance of insects or fungi. 

Young stands and areas which are in process of stocking are 
most effectively protected from fire by establishing and maintain- 
ing open fire lanes, free from straw and litter, completely around 
them or "on the exposed sides. A shallow furrow can be plowed 
every year on both sides of the lanes, and the intervening strip 
can be raked clear, or it can be burned during damp, quiet weather. 
In older stands the straw and litter can be raked off the lanes each 
autumn and used for stable beddings. Well established lanes, if 
they are free from stumps and shrubs, may conveniently be raked 
with a side delivery rake. By locating lanes at intervals through 
a large tract, as well as around it, it is separated into blocks whicli 
are individually protected. Where possible, roads and paths 
should be used for lanes. Since there is great danger of a serious 
lire during and immediately after lumbering, extra protective pre- 
caution should be taken at that time. A fire that occurs at that 
time will frequently destroy the pine seedlings, but the replace- 
ment of the hardwoods and shrubs takes place at once by sprout- 
ing. Repeated fires eliminate the pines. When timber is sold or 
when logging is done by contract, an enforceable fire penalty clause 
should be inserted in the contract, in order to obtain the necessary 
protection. 

The Federal Government under the terms of section 2 of 
the Weeks Law extends its co-operation to States in assisting them 
to protect the forested water-sheds of navigable streams from 
fire. In order to secure assistance of this kind a State must have 
provided by law for a system of forest fire protection and must 
have appropriated funds for the purpose. Scarcely a more im- 
portant step could be taken by the State of Virginia towards the 
conservation of its forests than the establishment of a fire pro- 



SHORTLEAF PINE IN VIRGINIA. 43 

lectivf system. The readiness of the Federal Government to chj- 
operate under the terms of this hiw as soon as the State itself 
makes a start is an incentive to immediate action. In the short- 
leaf pine area of ^"irginia the water-sheds of the Appomattox, 
James, Roanoke and Eapidan rivers coulil he protected hy such 
co-operation. 

Ins-ects.—The diinger of fire is greatest to seedling stands, hut 
the possibility of insect damage, although it is always present, 
increases after the trees are twenty years old. One of the most 
[)ernicious insects is the pine bark beetle, Dendr act onus frontalis, 
Zimnj which devastated the coniferous forest of middle and w^est- 
ern Virginia between 1888 and 1892. This species channels the 
inner bark in the middle part of the stem and eventually girdles 
the trees, thus killing tliem. Other beetles infest the wood of 
the living tree, and yet others attack only dead or dying trees. 
The fecundity of the pine bark beetle is so great that several large 
broods are produced in a single summer, and when conditions are 
favorable they propagate in enormous numbers and cause serious 
depredations. Pure stands in old fields invite destructive attacks, 
since in them the insects can readily spread from tree to tree. 

The best way to hold this insect in check is to keep the trees 
ill thrifty condition by preventing overcrowding, by removing 
wood which would serve as breeding places, and by cutting out in- 
fested trees. It is particularly desirable to maive these protective 
cuttings before the spring and early summer broods of the insects 
come out and spread. Infested trees should be promptly removed 
as soon as noticed. The removal of weak trees in thinning elimi- 
nates them as sources of breeding, while cutting low stumps and 
close utilization, or the piling and burning of tops — operations 
which are sometimes advisable for other reasons — remove much 
other wood. The cutting of live trees should be limited as far as 
possible to the winter, but dead trees can be cut at any time. 
Special care should be used in summer cutting not to leave freshly- 
cut tops touching live trees, and to remove promptly trees that 
have been killed by lightning. When cordwood or logs which are 
spring or summer cut cannot be promptly removed, they should be 
peeled or racked in the sun, that they may dry. Detailed infor- 
mation in regard to protection against this beetle is contained in 
Farmers' Bulletin, No. 476. 

Fungus Diseases. — The most important known fungus which 
attacks shortleaf pine is Tramefes pini, the cause of redheart. 



44 SHORTLEAF PINE IN VIRGINIA. 

This is a darlc brown siiutf-colored "punk'' which gains entrance 
into the heartwood of the upper part of the stem through knot 
holes, and into the lower part by wounds caused by falling trees, 
fire scars, (Plate VI, fig. 2), and insects. Trees which show the 
"punk" should be promptly cut. 

Pine stands are also exposed to damage from windstorms, and 
from sleet and wet snow. The damage by wind cannot be pre- 
vented. Fortunately, shortleaf pine, when it grows on deep soils, 
is anchored by a long, strong taproot, and is very windfirm. On 
shallow soils, particularly a hard-pan near the surface which 
checks the descent of the taproot, it windfalls badly. Slender trees 
are occasionally bent or even broken by wind. Frequent light thin- 
nings render the trees in such stands more windfirm. 

Sleet and wet snow are dangers against which there is no ade- 
quate protection. The weight of sleet and wet snow frequently 
breaks the leaders, and in crowded stands may bend many stems 
beyond recovery, break them, or even uproot them. The only pre- 
cautionary measure is to strengthen the resisting power of limbs 
and stems by thinning. Trees in young stands less than twenty 
years old are the most likely to be broken and bent, while trees in 
older stands, in which isolation is taking place, are the most apt 
to be overturned. P'requently. insect depredations follow this kind 
of damage. 




'^^Si 




N 









PLATE VI. 
A culled stand of mixed pine and hardwoods. The defecUve o^J^ '^ ^he left 
foreground Is partially shading groups of thrifty Pj-^ seed ings and sbo d be 
removed. The large pines in the background serve as seed trees. The seed-lngs 
are greatly exposed to tire. 



